25 Vegetable Seeds Free Brussel Sprouts Botanical name : Brassica oleracea var. gemmifera. Plant morphology : Brussels sprouts grow on a stalk and are made up of small, compact, cabbage-like heads. Each head is typically 1-2 inches in diameter and contains several layers of tightly-packed leaves. Soil and climatic requirements : Brussels sprouts grow best in cool weather and require moist, well-drained soil that is rich in organic matter. They prefer a slightly acidic soil pH of 6.0 to 7.0. Crop duration : Brussels sprouts take approximately 80-100 days from planting to harvest. Cropping season : Brussels sprouts are a cool-season crop and can be grown in both the spring and fall. Planting type : Brussels sprouts can be started indoors from seed or sown directly into the garden. Spacing : Brussels sprouts should be spaced 18-24 inches apart, with 30-36 inches between rows. Depth of sowing : Seeds should be planted OE to oe inch deep. Germination period : Seeds typically germinate within 7-10 days. Hours of sunlight required : Brussels sprouts require full sun t.